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Introduction
The prevalence of MCI (mild cognitive impairment) in subjects aged 70–89 years is estimated to be approximately 16% [1]. From a neuropsychological perspective, the goal is to identify cognitive domains and specific measures that can identify cognitively intact individuals at increased risk for subsequently developing MCI due to Alzheimer’s disease (AD). Episodic memory tasks (particularly delayed recall) have generally been considered the most consistent cognitive measure predictive of progression from age-appropriate memory performance to MCI and AD [2-4]. However, it has become increasingly evident that the preclinical period is also characterized by prominent difficulties in other cognitive domains including executive functions (attention), language, and working memory [5]. Studies have indicated that combining episodic memory tasks with language and executive function assessment is of value in identifying MCI at risk for progression to AD dementia [6]. Identifying MCI patients allows for monitoring progression, provides opportunity for appropriate counselling and offers a possible therapeutic window for intervention in the future.
In general, people have good memory for faces compared to other visual stimuli, and the eyes are particularly useful in helping us to remember faces. Subjective reporting of difficulty in remembering names of familiar people is common among subjects with MCI without overt difficulty in recognition of famous people. These aspects have however not been systematically studied in the MCI literature. Existing tests available have not been tailored to the Indian population and are available with mostly Western faces and names. A recent study indicated the deficits in the ability to learn novel face-name pairs among subjects with MCI and subjective cognitive impairment [7]. Forming an association between a random name and a face is a particularly difficult associative memory task, because names and faces are inherently semantically unrelated across verbal-visual domains, respectively, and have to be learnt. In addition to the hippocampus, the encoding of novel face-name associations likely requires the integration of several other brain regions, including the prefrontal and fusiform cortices [8]. In studies involving novel face-name pairs, it has been found that this encoding is subserved by a distributed functional network of brain regions, including the hippocampal formation, dorsolateral prefrontal cortex, pulvinar nucleus of the thalamus, fusiform gyrus, and adjacent areas of the visual association cortex [9].
It has been shown that...